Abrasive products are available in any of a variety of types, each generally being designed for specific applications and no particular type providing a universal abrading tool for all applications. The various types of abrasive products include, for example, coated abrasives, bonded abrasives, and low density or nonwoven abrasive products (sometimes called surface conditioning products). Coated abrasives typically comprise abrasive granules generally uniformly distributed over and adhered to the surface of a flexible backing. Bonded abrasives, a typical example of which is a grinding wheel, generally comprises abrasive material rigidly consolidated together in a mass in the form of a rotatable annulus or other shapes such as a block-shaped honing stone. Low density or nonwoven abrasive products typically include an open, lofty, three-dimensional fiber web impregnated with adhesive which does not alter the open character of the web and also adheres abrasive granules to the fiber surfaces of the web.
Bonded abrasive products such as grinding wheels are very rigid and, thus, not conformable to workpieces which have a complex surface. Coated abrasives are often used as abrasive belts or abrasive discs. Coated abrasive belts and discs have a high initial cut rate and produce a high surface roughness when new, but each of these properties drops off very rapidly in use. Coated abrasive products also have a somewhat limited degree of conformability when they are supported in an abrading machine. While use of abrasive belts on soft back-up wheels provides some degree of conformability, the lack of stretchability of the coated abrasive backing limits somewhat its conformability.
Abrasive products are used industrially, commercially, and by individual consumers to prepare any of a variety of materials for use or for further processing. Exemplary uses of abrasive products include preliminary preparation of a surface before priming or painting, cleaning the surface of an object to remove oxidation or debris and grinding or abrading an object to obtain a specific shape. In these applications, abrasive products may be used to grind a surface or workpiece to a certain shape or form, to abrade a surface to clean or to facilitate bonding of a coating such as paint, or to provide a desired surface finish, especially a smooth or otherwise decorative finish.
The grinding or finishing properties of the abrasive product may be tailored to some degree to provide a desired aggressive level of removal of material from a surface being abraded (“cut”), balanced with the need for a particular surface finish (“finish”). These needs may also be balanced with the need for a relatively long, useful life for the abrasive product. Typically, however, the cut and finish performance during the useful life of an abrasive product is not as consistent as desired. That is, during the useful life of typical abrasive products, the cut and finish of the product may vary with cumulative use. A need, therefore, exists for abrasive products with increased consistency of cut and finish. Such new products that also bridge the cut and finish performance between coated abrasive products and surface conditioning products would be especially useful.
Many methods of making abrasive products employ liquid or solvent-borne volatile organic binder materials which result in the unwanted creation of volatile organic compound (VOC) emissions. Some binder materials are water-borne and, thus, require an unwanted expense because of the additional energy cost in removing the water. Moreover, some methods of making abrasive products are complex, requiring multiple steps and complex equipment. A simplified process to produce such new abrasive products providing economical short product cycles and low or minimal volatile organic waste products would be particularly useful.
Thus, need exists for a flexible abrasive product which has a tailored cutting ability and a long, useful life which can be made in a simple method without producing undesirable amounts of volatile organic compound waste products.